Answer: Protons
The proton is a subatomic particle with a positive elemental electric charge equal in absolute value and opposite sign to that of the electron. This is due to the action of the electromagnetic force.
This particle was made known by Ernest Rutherford in the twentieth century (specifically in the year 1918).
It should be noted that protons are classified within the category of baryons which are subatomic particles formed by three quarks.